He may be the fastest 100 metres sprinter in World Junior Championship history
but, astonishingly, Adam Gemili has yet to decide whether his future lies
with athletics or professional football.

In his first major interview since his emergence as the new star of British sprinting, the 18 year-old from Dartford insists he is only halfway through a trial period when it comes to his athletics career, having decided last December to take 12 months out of football to see how far he could go on the track.

The answer is “all the way” on the evidence of his brilliant lifetime best of 10.05sec totake the world junior titlein Barcelona on Wednesday, and if he needs any more convincing there are always the London Olympics to remove any lingering doubts.

So rapid has the teenager’s progress been this summer, it is not inconceivable that he will be rubbing shoulders with Usain Bolt, Asafa Powell and Tyson Gay in the 100m final in London.

There is already plenty of talk of him becoming the first junior to run sub-10 seconds, particularly since he still has another year to go in the under-20 ranks. Four years ago in Beijing, 10.03sec was all it took to make the Olympic final.

But Gemili is not the kind of character to get carried away with hype, and he is sticking to his plan of making a rational career choice once the summer is over.

“I haven’t made a 100 per cent decision,” he said. “I’m going to see the rest of the year out. Obviously, it would be hard to turn away from athletics now after winning the World Juniors and going to the Olympics in a few weeks, but I don’t want to make that final decision until the end of the year.”

Given the praise being heaped on him by some of the sport’s greatest names, there can surely be only one decision to make.

American Maurice Greene, the former 100m world record-holder and Olympic champion who is commentating in Barcelona, joined the list of admirers when the pair met on Thursday morning.

Gemili said: “I spoke to Maurice and he said, ‘Looking at how long you’ve been in the sport, your technique is probably one of the best I’ve seen from a British sprinter’. That was such a lovely thing for me to hear coming from someone one from like him.”

When Gemili does sit down to ponder his future, he is sure to be consulting his mother, Sacha. It was at her insistence that he quit the Chelsea Football Club academy when he was 15, having been with the club since he was talent-spotted at the age of eight.

The hours spent travelling to and from Chelsea’s Cobham training ground were, he said, playing havoc with his GCSE studies and his mother decreed that enough was enough.

“My parents and I had a discussion and it was all to do with schooling and one or two other issues,” he said. “I was disappointed to leave Chelsea but life goes on, I guess. It was interfering with my school work very heavily and my mum was very strict about me getting an education. She’s my mum and she knows what’s best for me.”

There cannot be many young boys who would accept leaving a Premier League club with such equanimity, and therein lies one of the reasons why there are such high hopes for him on the track.

Michael Afilaka, who has been coaching him full-time since January, says his mental stability is as important as his natural physical ability.

“He’s a fantastically brought up kid and what we see a lot in coaching is a reflection of the way these lads are brought up as individuals,” said Afilaka. “He respects himself and he respects people, and that’s important.”

After leaving Chelsea, Gemili, who says he inherited his talents as a full-back from his Moroccan-born father, spent just over a year at Reading FC, where training commitments were more compatible with his school work. He then joined his local League Two club, Dagenham and Redbridge.

But his interest in athletics had already been kindled at his former school, Dartford Grammar, who entered him for the Kent School Games in 2010. He won the 100m, which qualified him to represent Kent at the English Schools Championships, and went on to win the silver medal.

That performance put him on the radar of UK Athletics and last year, having had no formal coaching, he won the 100m silver at the European Junior Championships in Tallinn, Estonia.

“People said I should join an athletics club but because I was concentrating on football, I didn’t join a club until about May 2011,” said Gemili.

“I just thought I’d give it a go for the summer and I ended up getting the European junior silver. I’d had no training really, so I was really pleased with it.”

His decision to put football on hold for a year came when he was offered his first professional contract by Dagenham and Redbridge in December.

“If I signed it, it obviously meant I had to stop athletics because I couldn’t do both, but I wanted to give athletics a go. I’d won the European junior silver in the summer, so I did want to see how far I could take it and how good I could become in athletics.

“I decided to devote the year to athletics and if it didn’t work out, I could still go back to football.”

Having trained with Afilaka a few times a week from last October, Gemili became a full-time athlete in January.

“We sat down and discussed what our realistic targets were and that was to make the World Juniors and hopefully make the final,” he said.

“I was totally raw. If you’d seen me run then, I had no understanding of athletics, no understanding of how to race or the different parts of the race. I didn’t know anything.”

The praise now being lavished on Gemili’s textbook technique is a testament to Aflika’s coaching ability and his own hard work over the past seven months. What is more, the teenager is convinced there is plenty more speed to come when he steps on to the Olympic stage in a few weeks’ time.

“I don’t think I’ve peaked,” he said. “I’ve been preparing for the World Juniors but I’ve been taking the Olympics into consideration. That’s why I didn’t do the 200 at these championships. We’re still working hard and there’s still a few more quick runs left in me.” Quick enough to make the Olympic final? Tantalisingly, Gemili does not rule it out.

“You’ve got a lot more sub-10 guys than four years ago, so I’d have to run very, very quick to sneak into the final, depending on how the rounds go,” he said.

“But I’m not really focusing on that. I’m just looking to go there and get a good experience and enjoy it.”